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Fifth Stage – ENT – Dr.Mushtaq – Lecture 7
Pharynx
Funnel shaped musculomembranous tube
Extended from the skull base to the oesophagus opposite the sixth cervical vertebra
1. Nasopharynx
2. Oropharynx
3. Hypopharynx.
Nasopharynx
• From base of skull to soft palate
• Walls
• Structures:
1. Pharyngeal opening of the eust.tube
2. Pharyngeal recess/ fossa of rosenmuller
3. Nasopharyngeal tonsil
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Oropharynx
• From soft palate to the upper border of the epiglottis
• Lat. Wall contains palatoglossal , palatopharyngeal
arches & palatine tonsil in between
Hypopharynx
• From upper border of epiglottis to the lower border of
the cricoid cartilage.
• From 3rd to 6
th
cx. vert.
• Supported by thyroid cartilage & thyrohyoid
membrane
Nerve supply
1. Motor:
* cranial part of the XI nerve & vagus n (X)
** glossopharyngeal n (IX) to stylopharyngeus muscle only
2. Sensory :
- maxillary n from the nasal part
- glossopharyngeal n.---oral part
- internal laryngeal n of the vagus from the laryngeal part
Blood supply
1. Ascending pharyngeal a.
2. Ascending palatine
3. Facial a.
4. Maxillary a
5. Lingual a
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Veinous drainage :
pharyngeal pluxes to int.jug.v.
Lymphatic drainage:
#- deep cx. Ln.
#- retropharyngeal
#- parapharyngeal Ln
- subepithelial lym. t. (Waldeyer`s ring):
1-palatine ts.
2-n/p ts ( adenoid)
3- lingual ts.
4- tubal ts.
5- lateral pharyngeal band.
Palatine tonsil
• Two masses of lymphoid tissue located in the lat. wall of the oropharynx between ant. & post.
Faucial pillars
• The free medial surface project into the cavity of pharynx and pitted by numerous small
opening lead into crypts in which the mucous glands are secreting
• Lat. Surface covered by fibrous tissue called capsule
Swallowing (deglutition)
• Oral phase
• Pharyngeal phase
• Oesophageal phase.
Oral phase
1. Preparatory stage:
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- food or drink in the mouth
- coordination of the lip, buccal,
mandibular, & tongue movements
- voluntary control
- cr ns ;- Vth (sens,mastication)
- VIIth( lip ,buccal)
- Xth (oropharyngeal sphinctor)
- XIIth (tongue )
2. Propulsive stage:
- bolus between the tongue &
hard palate
- contraction from the tip of
the tongue pushing against
the hard palate
- relaxation of the oropharyngeal
sphinctor ,rising of the soft palate &
dropping of the post. 1/3
rd
of the
tongue>>>bolus into the oropharynx
Pharyngeal phase
• pharyngeal peristalsis / propulsive force
• Two key elements;
1-tongue driving force
2-hypopharyngeal suction
* elevation of the Lyx
* change in the pressure at the cricopharyngeal sphinctor
* closure of Lyx & nyx
* relaxation of the cricopharyngeal sphinctor
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Oesophageal phase
• Relaxation of cricopharyngeal sph.
• Oesophageal peristalsis
Thank you,,,